Date: Sat, 31 May 2003 13:42:35 -0700 (PDT) From: Marcel Moolenaar <marcel@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/ia64/ia64 machdep.c Message-ID: <200305312042.h4VKgZDm038423@repoman.freebsd.org>
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marcel 2003/05/31 13:42:35 PDT FreeBSD src repository Modified files: sys/ia64/ia64 machdep.c Log: Make sure we have all the dirty registers in user frames on the backing store before we discard them. It is possible that we enter the kernel (due to an execve in this case) with a lot of dirty user registers and that the RSE has only partially spilled them (to make room for new frames). We cannot move the backing store pointer down (to discard user registers) when not all of the user registers are on the backing store. So, we flush the register stack IFF this happens. Unconditionally doing the flush is too costly, because the condition in which we need to flush is very rare. This change appears to fix the SIGSEGV that sometimes happen for newly executed processes and so far also appears to fix the last of the corruption. It is possible, although not likely, that this change prevents some other bug from happening, even though it is itself not a fix. Hence the uncertainty. We'll know in a couple of months I guess :-) Revision Changes Path 1.137 +12 -2 src/sys/ia64/ia64/machdep.c
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